Adsorption of phenol by bentonite

Area of Science:

• Environmental Science
• Materials Science
• Chemistry

Background:

• Phenol is a common pollutant in industrial wastewater.
• Effective adsorbent materials are needed for phenol removal.
• Bentonite is a clay mineral with potential adsorbent properties.

Purpose of the Study:

• To investigate bentonite's capacity for phenol adsorption from aqueous solutions.
• To evaluate factors affecting phenol adsorption and desorption by bentonite.
• To explore the influence of solvents on bentonite-phenol interactions.

Main Methods:

• Batch adsorption kinetics and isotherm studies were performed.
• Experiments varied contact time, initial phenol concentration, and solution pH.
• The effect of different solvents (water, cyclohexane, methanol) was assessed.

Main Results:

• Phenol adsorption increased with initial concentration and decreased with higher pH.
• Adsorption affinity was highest in cyclohexane, lowest in methanol.
• Methanol effectively desorbed phenol from bentonite.
• X-ray diffraction revealed bentonite structure alteration in cyclohexane.
• Adsorption decreased with increasing water in cyclohexane solutions.
• Hysteresis was observed during desorption in aqueous solutions.
• Langmuir and Freundlich models fitted the equilibrium data.

Conclusions:

• Bentonite demonstrates significant potential for phenol removal from aqueous solutions without modification.
• Solvent choice critically impacts phenol adsorption and desorption efficiency.
• Understanding adsorption-desorption mechanisms is key for wastewater treatment applications.